1. Field of the Invention
The present invention relates to a liquid crystal display (LCD) device and an electronic apparatus provided therewith.
2. Description of the Related Art
As a display device, there is known a reflective type display device for displaying an image by using reflected light of incident light entered from outside, as well as a transmissive type display device for displaying an image using transmitted light of backlight from a rear surface of a screen. The reflective type display device has advantageous features such as low power consumption and viewable screen or monitor even in bright environment. Furthermore, as a display device having a feature of the reflective type display device and a feature of the transmissive type display device, there is known a transflective type liquid crystal display device. In the transflective type liquid crystal display device, an image is displayed by using a backlight in a dark environment, or an image is displayed by using reflected light of external light in a bright environment.
There have been proposed some display devices in which an anisotropic scattering film such as Light Control Film (LCF) capable of increasing the reflectance of light is disposed at an observation surface side of the display device in order to improve an illuminance of an image (Japanese Patent Application Laid-open Nos. 2007-249182, 2007-249181, and 2007-114756). The anisotropic scattering film has a scattering center (scattering central axis) in a direction inclined by a predetermined angle from a normal line direction of the observation surface of the display device. The light transmitted through the anisotropic scattering film along the scattering center becomes scattered light. In order to improve a view angle effect (view angle dependency) of the display device, the scattering center is directed so that the contrast ratio of the display device is maximized.
In some display devices, there is proposed a direct backlight unit as a backlight unit disposed at a rear surface of the screen (Japanese Patent Application Laid-open No. 2008-52132). In the backlight unit, an anisotropic light diffusing adhesive layer is disposed between a light diffusion plate and a rod-like light source. In order to obtain a uniform light from an irradiation surface of the light diffusion plate, a longitudinal direction of needle-like filler contained in the anisotropic light diffusing adhesive layer and a tube axis direction of the rod-like light source are directed to an approximately same direction.
In the reflective type display device or the transflective type display device for displaying an image by using a reflected light of an external light, the reflected light emitted from a light emitting surface is transmitted through an anisotropic scattering member such as an anisotropic scattering film, when such an anisotropic scattering member is disposed on the light emitting surface from which the reflected light is emitted. In this case, if there is a gap between the light emitting surface and the anisotropic scattering member, a light path length of the reflected light becomes longer. Thereby, the reflected light is likely to expand in a surface or plane and it causes a blurred image. Furthermore, when an emitting direction of the reflected light emitted from the light emitting surface crosses the scattering center of the anisotropic scattering member at a considerable angle, the reflected light is emitted without scattering due to a property of the anisotropic scattering member. Thereby, the directional dependency of the reflected light is increased.